Hakyemez Bahattin, Yildirim Nalan, Gokalp Gokhan, Erdogan Cuneyt, Parlak Mufit
Department of Radiology, Uludag University School of Medicine, Gorukle, Bursa, Turkey.
Neuroradiology. 2006 Aug;48(8):513-20. doi: 10.1007/s00234-006-0094-z. Epub 2006 Jun 20.
Atypical/malignant meningiomas recur more frequently then typical meningiomas. In this study, the contribution of diffusion-weighted MR imaging to the differentiation of atypical/malignant and typical meningiomas and to the determination of histological subtypes of typical meningiomas was investigated.
The study was performed prospectively on 39 patients. The signal intensity of the lesions was evaluated on trace and apparent diffusion coefficient (ADC) images. ADC values were measured in the lesions and peritumoral edema. Student's t-test was used for statistical analysis. P<0.05 was considered statistically significant.
Mean ADC values in atypical/malignant and typical meningiomas were 0.75+/-0.21 and 1.17+/-0.21, respectively. Mean ADC values for subtypes of typical meningiomas were as follows: meningothelial, 1.09+/-0.20; transitional, 1.19+/-0.07; fibroblastic, 1.29+/-0.28; and angiomatous, 1.48+/-0.10. Normal white matter was 0.91+/-0.10. ADC values of typical meningiomas and atypical/malignant meningiomas significantly differed (P<0.001). However, the difference between peritumoral edema ADC values was not significant (P>0.05). Furthermore, the difference between the subtypes of typical meningiomas and atypical/malignant meningiomas was significant (P<0.001).
Diffusion-weighted MR imaging findings of atypical/malignant meningiomas and typical meningiomas differ. Atypical/malignant meningiomas have lower intratumoral ADC values than typical meningiomas. Mean ADC values for peritumoral edema do not differ between typical and atypical meningiomas.
非典型/恶性脑膜瘤比典型脑膜瘤更易复发。在本研究中，探讨了扩散加权磁共振成像在非典型/恶性与典型脑膜瘤鉴别诊断以及典型脑膜瘤组织学亚型判定中的作用。
对39例患者进行前瞻性研究。在追踪图像和表观扩散系数（ADC）图像上评估病变的信号强度。在病变及瘤周水肿区域测量ADC值。采用学生t检验进行统计学分析。P<0.05认为具有统计学意义。
非典型/恶性脑膜瘤和典型脑膜瘤的平均ADC值分别为0.75±0.21和1.17±0.21。典型脑膜瘤各亚型的平均ADC值如下：脑膜皮型，1.09±0.20；过渡型，1.19±0.07；纤维型，1.29±0.28；血管瘤型，1.48±0.10。正常白质为0.91±0.10。典型脑膜瘤与非典型/恶性脑膜瘤的ADC值差异有统计学意义（P<0.001）。然而，瘤周水肿ADC值之间的差异无统计学意义（P>0.05）。此外，典型脑膜瘤各亚型与非典型/恶性脑膜瘤之间的差异有统计学意义（P<0.001）。
非典型/恶性脑膜瘤与典型脑膜瘤的扩散加权磁共振成像表现不同。非典型/恶性脑膜瘤的瘤内ADC值低于典型脑膜瘤。典型脑膜瘤与非典型脑膜瘤的瘤周水肿平均ADC值无差异。
